The Rhodos Coast is a location on the western coast of the Holy Kingdom of Faerghus.
The Rhodos Coast features a cemetery that is held sacred by the Church of Seiros. In Imperial Year 1180, the Western Church seized the cemetery in a direct provocation of the Central Church. Seteth was tasked with reclaiming the cemetery, but Flayn insisted that she and Byleth accompany her brother out of fear for his safety.
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The cemetery's importance to the Church lies in the fact that it is the burial place of Flayn's mother. Flayn is revealed to be Saint Cethleann herself, while Seteth is Saint Cichol and thus Flayn's father.